If at any point you develop a fever while on study, blood (about 1 teaspoon) and urine will be collected to check for infection according to standard evaluation of patients with fever to look for underlying infectious causes. You may also have a chest x-ray. If it is abnormal or if you have symptoms (cough, shortness of breath, nasal congestion), you may need a computed tomography (CT) scan of the chest and/or sinuses. That will be done within 3 days of developing a fever. If the doctor thinks it is needed, you will than have another CT scan 2 weeks later and at any other point that the doctor thinks it are needed to check for infection.